1. Field of the Invention
The present invention relates to a structure for supporting an sleeve to optically connect an optical connector adapter that is reduced in the number of parts, and to an optical connector adapter using same.
2. Description of the Prior Arts
The conventional optical connector adapter represented by an SC type optical connector adapter incorporates an optical connection sleeve to provide alignment between opposite ferrules having therein an optical fiber and to optically couple between the optical fibers. The optical connection sleeve is held by a sleeve holder that is axially divided into two. The sleeve holder is in turn held by a housing axially divided into two.
Herein, FIG. 11 and FIG. 12 show an outside appearance and longitudinal view of an SC type connector adapter. As shown in the figures, an optical connection sleeve 101, such as a split sleeve having a slit, is incorporated in a pair of sleeve holders 102 and 103. Also, the pair of sleeve holders 102 and 103 are held by a pair of housings 104 and 105.
The sleeve holders 102 and 103 have respective support holes 102a and 103a to incorporate therein the optical connection sleeve 101. The support holes 102a and 103a each have, at one end, a stop 102b, 103b provided in a circumferential direction and having a circumferential edge inwardly projecting. The stops 102b and 103b are to abut against an end face of the optical connection sleeve 101 to regulate the optical connection sleeve 101 from moving in an axial direction. Also, the pair of sleeve holders 102 and 103 are of a structure to clamp axially oppositely the optical connection sleeve 101. Consequently, the axially inner ends are of a fitting structure, at circumferential edges of which are provided flanges 102c and 103c. The sleeve holders 102 and 103 each have, in radially opposite positions, a pair of claw portions 102e and 103e having respective engagement claws 102d and 103d at their tips.
On the other hand, the housings 104 and 105 respectively have flanges 104a and 105a to connect the both and support grooves 104b and 105b formed in inner surfaces that clamp and support the flanges 102c and 103c of the sleeve holders 102 and 103. By welding the flanges 104a and 105a of the housings 104 and 105 through ultrasonic waves, etc., the sleeve holders 102 and 103 are clamped and held in the support grooves 104b and 105b formed in the inner peripheral surface of the housings 104 and 105. Also, the housings 104 and 105 each have, on an opposite side to the flange 104a, 105a, an opening 104c, 105c in which an optical connector plug can be inserted.
Incidentally, one housing 105 is provided, at an outer peripheral surface, with a plate 106 as a metal-make engagement spring to engage with an optical connector mount panel.
As described above, the conventional optical connector adapter requires to implement ultrasonic welding, screwing and riveting after combining the five parts. This results in a problem with increased assembling operation and hence mount-up of cost. Also, many parts leads to increase of material cost.
Meanwhile, there also is a problem of difficulty in enhancing the accuracy of positioning the left and right housings. There is possibly a case of causing change in optical connection stability, particularly in reproducibility of optical loss upon repeating connector connection and disconnection or in optical loss when applying tension or bending to an optical fiber cord.
It is an object of the present invention to provide, in view of the above circumstances, a support structure of an optical connection sleeve for an optical connector adapter, and an optical connector adapter, which are reduced in the number of parts and improved in the accuracy of positioning left and right housing.
A first form of the present invention to solve the problem lies in an optical connector adapter having a penetration hole for incorporate and support an optical connection sleeve, comprising: a sleeve holder integrally provided with a first cylindrical member forming lengthwise one end of the penetration hole; a housing integrally provided with a second cylindrical member forming the lengthwise other end of the penetration hole and having a shape to internally hold the sleeve holder; engagement means for engaging the sleeve holder and the housing in a state that the first cylindrical member and the second cylindrical member at respective one ends are abutted against each other; and engagement convex portions integrally formed projecting radially inward at respective other ends of the first cylindrical member and the second cylindrical member to regulate the optical connection sleeve from moving in an axial direction.
A second form of the invention lies in an optical connector adapter, wherein in the first form the engagement means has an engagement pin inserted and held in the housing in a state that the sleeve holder is assembled with the housing, and an engagement portion integrally provided on the sleeve holder to engage the engagement pin in a state combined with the housing.
A third form of the invention lies in an optical connector adapter, wherein in the first form the engagement means has an engagement claw provided on any one of the housing and the sleeve holder to be elastically deformable in an radial direction, and an engagement recess provided on the other to engage the claw.
A fourth form of the invention lies in an optical connector adapter, wherein in any of the first to third forms the housing is formed with an aperture to be coupled with an optical connector plug.
In the optical adapters of the invention, the optical connector adapter can be assembled by merely assembling the housing with the sleeve holder through the engagement means in a state an optical connection sleeve is internally assembled.
A fifth form of the invention lies in an optical connector adapter, each pair of claw portions are provided appositely of shorter sides of the flange such that they sandwich the first cylindrical member and the housing second cylindrical member, and have a pair of claw portions and having engagement claws at tips. These claw portions are to couple with an optical connector plug. Further the claw portion having a thickness continuously decreasing toward the engagement claw.
The claw portion of the above form can reduce the strength of deforming the claw portion when coupling a connector plug. As a result, an optical connector adapter is available that is easy to couple.
A sixth form of the invention lies in an optical connector adapter, wherein in the fifth form the claw portion is in a concave form on an outer periphery side of the cylindrical member. By forming in a concave-form curved surface, it is possible to prevent fatigue and breakage in the claw portion due to repetition of connector plug connection and disconnection.